Printing press cylinder



NOV; 938- H. P. SCHMIDT I 2, 5

PRINTING mass cymmma Original Filed Aug. 14, 1 934 2 Sheets-Sheet 1 INVENTOR 8% P ATl'O RNEY No 33- P. scams-r 2,135,150

- PRINTING PRESS CYLINDER I Original Filed Aug. 14, i934 2 Shoots-811601. '2

wv m n BYM z ATTORNEY PetemediNJv. 1,1938

PATENT OFFICE j r. Schmidt, New York, N. Y., asaignor to H. H. Heinrich, Inc., New York, N. 1., a corporatlon New York Application August 14, 1934, Serial No. 139,745

Renewed March as. 193':

6 (Cl. Mil-415.1)

This invention relates to improvements in printing press cylinders and'rneans for mounting printing plates thereon. In particular my invention relates to that type of. printing cylinder which employs rubber or other resilient sur; faces and which is used in the process commonly known as rubber'plate printing. Such cylinders are particularly adapted for use in rubber plate printing presses using quick drying aniline inks, this combination providing high speed production with the minimum of make ready time and without requiring the services of a highly skilled pressman as in other forms of printing presses. In rubber plate printing presses a web of paper is passed between an impression cylinder and the cylinder carrying the rubber or other resilient printing surface in order to impress the printing surface upon the paper. It is a desideratum that the surface of the rubber plate be continuous in order that the printing therefrom be unbroken; Maintaining a continuous and unbroken surfaced rubber plate has heretofore been accomplished by having continuous and unbroken surfaced cylinders with the rubber or resilient surface processed directly on to the cylinder surface. It is obvious however that in such cylinders that for each change of design a separate cylinder is required or that the design then on the cylinder be destroyed when replacing it with another. 7 My invention further relates to the provision of segmental cylinders with' means for tightly stretching a metallic printing plate around the circumference thereof when the segments are drawn together and in such manner as to present a substantially continuous and unbroken printing surface.

It has heretofore been proposed to furnish a segmental cylinder with means for tightly stretching a metallic printing plate around 'the circumference of the cylinder when the segments are drawn together. Such devices are shown in United States Patents Nos. 1,730,122, 1,795,700, 1,795,702 and 1,860,765. These devices disclosed in the prior art do-not, however, provide an unbroken printing surface such as that provided. in printing press cylinders where the designis processed directly on or into the surface of a cylinder having a continuous and unbrokensurface, in that the metallic printing plate in its entirety is bent inwardly over rounded corners of the outer meeting edges of the cylinder segments, or the construction is otherwise such that the plate surface is not continuous. In such construction an inactive space of appreciable 55 width is disposed longitudinally of the plate surto' a segmental cylinder.

- in the appended claims.

rubber or other resiliently surfaced plate re- 'face.and a blank space respect to the printing results. v I

It is thereforethe principal object of my invention to provide a printing press cylinderhaving a printing plate removably mounted thereon ina-manner that will present the equivalent .of an unbroken printing surface. I

It is another object of my invention to provide a printing press cylinder having a rubber or other resiliently surfaced printing plate removably mounted thereon in a manner that will present the equivalent of an unbroken printing surface.

Another object of my invention is to provide novel means of attaching a rubber printing plate Another object of my invention is to provide novel means of drawing together segments of a divided cylinder. 1 v

'IAnotherobiect of my invention is to provide new and novelmeans for securing a segmental cylinder'to its supporting and operatingshaft.

with these and other objects in view which will readily appear as the nature of the invention is better understood, the same consists in the improved construction and novel arrangement and combination of parts which .will be. hereinafter fully described and fully'pointed out In the accompanying drawings has been illustrated a simple and preferred form of the.invention, it being understood however that no limitation is necessarily made to the precise structural details therein shown, but that changes, alterations and modifications within the scope of the appended claims may be resorted to when desired.

movably mounted thereon;

Fig.2 shows one of the halves of the cylinder illustrated inFig. 1, the shaft upon which the completely assembledcylinder is placed, the relationship of the rubber or other resiliently surfaced printing plate to the cylinder, and a sectional view of the retaining collars;

Fig. 3 is a sectional view taken through A-A of Fig. 1 looking in the direction of the arrows; 60

Fig. 4 is an end view of a completely-assembled cylinder as shown in Fig. l, and

Fig. 5 is an end view of two halves of the cylinder alone. I

' Referring to the drawings in. detail, wherein spending parts throughout the several views:

I is the two halves of a hollow cylinder, each having end walls 2. The end walls 2 of each cylinder half are provided with slightly less than half of a bore 3 suitable for clamping engagement with shaft 4 on which the two cylinder halves I are to be mounted. The printing plate 5 which in one form thereof is shown as having a rubber or other resilient printing surface consists of a base 8 composed preferably of fine mesh screen wire to which a rubber surface is vulcanized, although a thin sheet of metal or fabric such as heavy canvas or other suitable material may be used for base 8. In some cases it may be desired to use a thin all metal plate, with or without base cylinder halves I when they are removed from the shaft 4. The abutting ends I of the rubber portion of the plate 5 are placed to extend slightly beyond the edges 8 of the cylinder halves I, to compensate for the thickness of the base 8, and the ends 8 of the base 6 are turned inwardly of the edges 8 of the cylinder halves I where they are secured by compression between bars Ill and the surfaces II of cylinder halves I by screws I2. It isto be. noted that edges 8 of the cylinder halves I are quite sharp, being preferably just short of a cutting edge and that due to sloping the cylinder walls as at 8', clearance is provided between the turned in portions of base .8 except at edges 8. The sharp edges 8 of the cylinder halves I are also important when it is desired to use a thin all metal printing plate since the meeting line, formed when the edges of such a plate are bent over and held as shown, is practically indistinguishable. The cylinder .halves I are then placed upon the shaft 4 and a spacer plate ll of approximately the same thickness as the two turned-in ends of base 6 is inserted between the edges I8 of the cylinder halves I. The cylinder halves I are then closed together sufllciently .to permit collars I3 to be slid over the reduced end portions I4 or the cylinder halves I. The bars III extend outwardly of the cylinder halves I and project into the cut-out portions I5 of the collars I3. Through one wall of the cut-out portions I5 of the collars I3 projects screws I8 which engage the outwardly extending ends of one of the bars III. The outwardly extending ends of the otherbar I0 engage the opposite walls of the cut-out portions I5 of the collars I3 to those through which the screws I6 project. Turning the screws lars I3. Byhaving the printing plate 5 slightly,

shorter in dimension than the circumference of the cylinder it is tightly stretched around the cylinder when thecylinder halves I are forced together as described. It will be obvious that screws I6 can be used to compress the turned-in portion 9 of the base 6 and the abutting portions I of the plate.5 to any extent necessary in order to form the equivalent of a continuous unbroken printing surface. In event of any irregularity in the meeting of abutting portions 1 of plate 5, trimming or pressing of the edges may be resorted to in order to provide an' indistinguishable meet- 2,185,150 similar reference characters designate correing line. It will also be obvious' that I can provide like means to those shown for engaging ends of a plate at I8 where spacer I1 is now provided removably mounted thereon in a manner that will present the equivalent of an unbroken printing surface, and thatI have provided new and novel means for attaching such a printing plate to a. divided cylinder, with an indistinguishable meeting line at the abutting edges thereof, and that I have provided novel means for drawing the halves of a divided cylinder together, and for securing the divided cylinder to its supporting ;and operating shaft.

, 1. A' printing cylinder composed of two halves of a cylinder, means mounted in each of thecylinder halves for clamping an'end of a printing plate, and means for forcing the cylinder halves together, said last named means consisting of collars mounted on reduced end portions of said cylinder halves and screw means in said collars engaging extended portions of the printing plate clamping means.

2. A printing cylinder comprising two semicylindrical parts having opposed parallel peripheral edges and cut away portions beveled inwardly therefrom providing clearance progressively increasing away from said edges and toward the axis of rotation of the cylinder, a printing plate backing disposed around the cylinder ported by the portions of the backing compressed between said opposed peripheral edges of said cylinder parts, and means for forcing the cylinder parts together to effect the compression of the portions of the printing plate backing as aforesaid.

3. In a printing cylinder, a plurality of cylinder segments having opposed parallel peripheral edges and cut away portions beveled inwardly therefrom providing clearance progressively increasing away from said edges and toward the axis of rotation of the cylinder, a resiliently surfaced printing plate extending around said cylinder, said printing plate having a basememberthe ends of which are turned inwardly of said cylin- .der and through said clearance and compressed between the opposed parallel peripheral edges of the segments thereof, the ends of the resilient portion of said printing plate being abutted together under compression and supported by the compressed portions of said base member to form an unbroken continuously supported printing surface.

4. In a printing cylinder, 8. cylinder'comprising a plurality of cylinder segments assembled together and having opposed parallel walls providing for meeting only at the periphery of the.

cylinder, a resiliently surfaced printing plate having a flexible base member extending around said cylinder, said base member having end porto form a continuous surface, and the meeting edges of the resilientportion of said printing plate being compressed together to form a continuous printing surface, the compressed end por-- tions of said base member providing rigid continuous support for the meeting edges of said resilient portion of said printing plate.

5. In a printing cylinder, the combination of a' printing plate having a surface of resilient material and a base member, disposed around a cylinder composed of a plurality of segments, means for. mounting said segments upon'a shaft to form the cylinder comprising protruding shoulders on the cylinder segments extending longitudinally along the shaft, collars adapted to ride on said shoulders, screw means on said collars for pressing against longitudinally extending strip-like members, a pair of said members, said screws in said collars being adapted to draw the backing of said printing plate tightly about said segments and to compress the meeting ends of the resilient material so .as to form a' continuous and uniform printing circumferenee'about the segments. l

'6. In a printing cylinder, the combination of two cylinder halves assembled together to form a cylinder, said cylinder halves having opposed cut away beveled portions in the circumferenv a g, 7 8,185,150

tions compressed at the periphery of said cylinder mounted upon reduced end portions of said cylina base member the opposite ends of which are turned inwardly of and secured inside the cylinder halves and portions of which are compressed between the peripheral meeting edges of solid cylinder halves and the resilient surface of said printing plate having abutting edges meeting un'.

der compression and overlying the compressed portions of said base member, and collars der halves, said collars having means for forcing together said cylinder halves to tightly draw said base member around said cylinder, halves,

compress portions of the base member between the peripheral meeting edges of said cylinder halves, and compress together the abutting ends of the resilient portion of said printing plate overlying the compressed portionsof said base member, said compressed portions of said base member providing rigid support for the abutting -25 ends of the resilient portion of said printing plate so that a circumferentially continuous design is printed therefrom.

' 1 t HARRY P. SCHMIDT. 

